1. Field of the Invention
The present invention relates to a copper alloy material and a method for fabricating the same, in more particular, to a copper alloy material with excellent bending characteristics and a method for fabricating the same.
2. Related Art
In recent years, parts or components used for various electric and/or electronic devices have been miniaturized in accordance with miniaturization, reduction in thickness, and lightweighting of the various electric and/or electronic devices. Further, the miniaturization and the reduction in a pitch between electrodes of a terminal or connector of the parts have been desired in accordance with the miniaturization of the parts or components. Thickness of electrode materials for various parts is reduced compared with that in conventional electrode materials, as a result of the miniaturization of such a part. Herein, it is required to use a material with high spring property as the material of the electrode and the like, so as to keep reliability in electrical connection even in a thin electrode. In order to securely provide the high spring property, it is necessary to sufficiently increase strength and proof stress of the material.
Furthermore, in accordance with the miniaturization of the parts, it is also demand to fabricate parts with complicated shapes by an integral molding. Therefore, materials that can be applied to bending process under a severe condition are strongly demanded. In addition, Joule heats generated in the electrode and the like are increased by the effect of an increase in the number of the electrodes and an increase in electric current to be supplied, in accordance with provisions of higher functions of the electric or electronic devices. Therefore, a demand for using the materials with excellent electric conductivity compared with the conventional materials is increased. In other words, it is required that the materials composing the terminals or connector parts used for the electric or electronic devices have excellent electric conductivity as well as high strength, high proof stress and excellent bending characteristics.
As a conventional material with the high strength, excellent electric conductivity and low cost, a copper alloy such as Cu—Ni—Si based alloy has been used. For example, Japanese Patent Laid-Open No. 2008-13836 (JP-A 2008-13836) discloses a copper alloy sheet which comprises Ni and Si, and further comprises Sn and Mg as needed, the balance being Cu, in which a ratio of a diffraction intensity obtained from {220} of the copper alloy sheet to a diffraction intensity obtained from {220} of a pure copper standard powder and a ratio of a diffraction intensity obtained from {200} of the copper alloy sheet to a diffraction intensity obtained from {200} in the pure copper standard powder that are obtained by 2θ/θ measurement by X-ray diffraction are determined to fall within respective predetermined ranges.
JP-A 2008-13836 provides the copper alloy sheet in which anisotropy in the tensile strength and bending characteristics are improved.
However, in the copper alloy sheet disclosed by JP-A 2008-13836, since the diffraction intensities in specific crystal faces are used for 2θ/θ measurement by the X-ray diffraction, only a partial information of plural crystal faces that are parallel to a surface of the copper alloy sheet is obtained, so that there is the case where the bending characteristics of the copper alloy sheet cannot be appropriately controlled.